Semiconductor structure and method of manufacture

Abstract

In various embodiments, semiconductor structures and methods to manufacture these structures are disclosed. In one embodiment, a capacitor embedded in a dielectric material below the surface of a semiconductor substrate is disclosed. Other embodiments are described and claimed.

1. A semiconductor structure, comprising:
 a semiconductor material comprising a conductive substrate; 
 a first dielectric material below a surface of the semiconductor material; 
 one or more trenches in the first dielectric material, wherein the conductive substrate is disposed below the trenches of the capacitor and separated from the trenches of the capacitor by the dielectric material; 
 a capacitor formed in the one or more trenches, the capacitor including a first conductive material formed over the semiconductor material surface and lining the sidewalls and bottoms of the one or more trenches formed in the first dielectric material to provide a first plate of the capacitor, a second dielectric material formed over the first plate of the capacitor and a second conductive material formed within the second dielectric material to provide a second plate of the capacitor; 
 wherein the second conductive material comprises a substantially planar portion, the substantially planar portion being disposed over two or more of the trenches external to the trenches, and wherein the second conductive material comprises a plurality of extensions that extend from the substantially planar portion into the trenches, wherein in a given trench the extension is surrounded on opposite sides of the trench by first conductive material; and 
 first and second electrical interconnects to the capacitor extending above a surface of the second dielectric material, the first electrical interconnect coupled to the first conductive material, and the second electrical interconnect coupled to the second conductive material. 
 
     
     
       2. The semiconductor structure of  claim 1 , wherein the first conductive material comprises a doped polysilicon and the second conductive material comprises a doped polysilicon. 
     
     
       3. The semiconductor structure of  claim 1 , wherein the second dielectric material comprises silicon nitride or oxide. 
     
     
       4. The semiconductor structure of  claim 1 , wherein the second dielectric material comprises a plurality of dielectric materials. 
     
     
       5. The semiconductor structure of  claim 4 , wherein the plurality of dielectric materials comprises a first layer of oxide over the first conductive layer, a second layer of silicon nitride over the first layer of oxide, and a third layer of oxide over the second layer of silicon nitride. 
     
     
       6. The semiconductor structure of  claim 1 , wherein the first conductive material comprises a conductive silicide. 
     
     
       7. The semiconductor structure of  claim 1 , wherein the second conductive material comprises a continuous conductive material. 
     
     
       8. The semiconductor structure of  claim 1 , further comprising a third conductive material electrically coupled to the second conductive material. 
     
     
       9. The semiconductor structure of  claim 1 , wherein the one or more trenches each extend at least about three microns or greater below the surface of the semiconductor material. 
     
     
       10. The semiconductor structure of  claim 1 , wherein a portion of the first dielectric material between the semiconductor material and the bottom of a first trench of the one or more trenches has a thickness of at least about 0.7 μm or greater. 
     
     
       11. The semiconductor structure of  claim 1 , further comprising an active circuit element, wherein a portion of the active circuit element is in the semiconductor material and wherein the first dielectric material surrounds or partially surrounds the portion of the active circuit element. 
     
     
       12. The semiconductor structure of  claim 1 , further comprising forming at least a portion of an electrically conductive material over at least a portion of the first dielectric material. 
     
     
       13. The semiconductor structure of  claim 1 , wherein a sidewall of a first trench of the one or more trenches comprises stress relief elements comprising s-shaped, wavy, hexagonal, octagonal, rectangular, triangular, or spring-like features, or combinations thereof. 
     
     
       14. A semiconductor structure, comprising:
 a semiconductor material; 
 a first dielectric material below a surface of the semiconductor material; 
 one or more trenches in the first dielectric material; 
 a capacitor formed in the one or more trenches, the capacitor including a first conductive material formed over the semiconductor material surface and lining the sidewalls and bottoms of the one or more trenches formed in the first dielectric material to provide a first plate of the capacitor, a second dielectric material formed over the first plate of the capacitor and a second conductive material formed over the second dielectric material to provide a second plate of the capacitor; 
 wherein a sidewall of a first trench of the one or more trenches comprises stress relief elements comprising s-shaped, wavy, hexagonal, octagonal, rectangular, triangular, or spring-like features, or combinations thereof. 
 
     
     
       15. Wherein the stress relief elements are periodically disposed. 
     
     
       16. Wherein the stress relief elements are non-periodically disposed.